This invention relates generally to medical devices and methods of detection and treatment of cancer, and more particularly to minimally invasive medical systems including a radiation detecting probe for locating radioactively tagged tissue, e.g., a "sentinel" lymph node, within the body of the patient and for retrieving or removing that tissue.
The use of radioactive materials to tag tissue within a patient for effecting its localization and demarcation by radiation detecting devices has been disclosed in the medical literature for at least forty years. Significant developments in the localization and demarcation of tissue bearing radioactive isotope tags for diagnostic and/or therapeutic purposes have occurred since that time. In fact, it is now becoming an established modality in the diagnosis and/or treatment of certain diseases, e.g., cancer, to introduce monoclonal antibodies or other tumor or lymph node localizing agents tagged with a radioactive isotope (e.g., Technetium 99 m, Indium 111, Iodine 123, and Iodine 125) into the body of the patient. Such radiopharmaceuticals tend to localize in particular tissue, such as the cancerous tissue, so that the gamma radiation emitted by the isotope agent can be detected by a radiation detector, e.g., a probe. In particular, the radiation detector or probe is disposed or positioned adjacent portion of the patient's body where the cancerous tissue is suspected to be in order to detect if any radiation is emanating from that site. If it is this indicates that cancerous tissue is likely to be found at that site.
Prior art, hand-held, radiation detecting probes particularly suitable for such cancer-finding applications are commercially available from the assignee of this invention, CareWise Medical Products, Inc. under the trademark C-TRAK. In U.S. Pat. Nos. 4,959,547 and 5,036,201 assigned to the same assignee as this invention there are disclosed hand-held radiation detecting probes having collimating means to establish the field of view or "solid angle of acceptance" of the probe. In U.S. Pat. Nos. 5,119,818 and 5,170,055, also assigned to the same assignee as this invention, there are disclosed hand-held radiation detecting probes and accessories optimized to biopsy radio-labeled tissues. In U.S. Pat. No. 4,801,803 (Denen et al.) there is also disclosed a hand-held radiation detecting probe.
In the diagnosis and treatment of breast cancer and prostate cancer a radiopharmaceutical can injected adjacent a detected tumor site, e.g., within the breast, to migrate to the closest draining lymph node (the "sentinel" node) so that localization of that node and its examination can be readily effected in order to evaluate the extent, if any, of metastasis of the cancer. Heretofore, no minimally invasive instrument, e.g., radioactivity detection probe, has existed to not only detect or localize the radioactively tagged tissue, e.g., the sentinel node, but also to engage or otherwise ensnare or trap it so that it can be removed for analysis.
It is a general object of this invention to provide a minimally invasive surgical probe and method of use which overcomes the disadvantages of the prior art.